Chromium and Diabetes

Chromium is an essential trace mineral that helps the body maintain normal blood sugar levels. In addition to its well-studied effects in diabetes, preliminary research has found that its supplementation also improves glucose tolerance in people with Turner’s syndrome—a disease linked with glucose intolerance.

The mineral may also play a role in increasing HDL (“good”) cholesterol, while lowering total cholesterol levels.

Sources

The best source is true brewer’s yeast. Nutritional yeast and torula yeast do not contain significant amounts and are not suitable substitutes for brewer’s yeast. It is also found in grains and cereals, though much of it is lost when these foods are refined. Some brands of beer contain significant amounts of the mineral.

Side effects or Interactions

In supplemental amounts (typically 50–300 mcg per day), the mineral has not been found to cause toxicity in humans. While there are a few reports of people developing medical problems while taking it, a cause-effect relationship was not proven. One study suggested that the mineral in very high concentrations in a test tube could cause chromosomal mutations in ovarian cells of hamsters. Chromium picolinate can be altered by antioxidants or hydrogen peroxide in the body to a form that could itself create free radical damage. In theory, these changes could increase the risk of cancer, but so far, its intake has not been linked to increased incidence of cancer in humans.

The supplementation may enhance the effects of drugs for diabetes (e.g., insulin, blood sugar-lowering agents) and possibly lead to hypoglycemia. Therefore, people with diabetes taking these medications should supplement with it only under the supervision of a doctor.

One report of severe illness (including liver and kidney damage) occurring in a person who was taking 1,000 mcg of the mineral per day has been reported. However, its supplementation was not proven to be the cause of these problems. Another source claimed that there have been reports of mild heart rhythm abnormalities with excessive ingestion. However, no published evidence supports this assertion.

Three single, unrelated cases of toxicity have been reported from use of chromium picolinate. A case of kidney failure appeared after taking 600 mcg per day for six weeks. A case of anemia, liver dysfunction, and other problems appeared after four to five months of 1,200–2,400 mcg per day. A case of a muscle disease known as rhabdomyolysis appeared in a body builder who took 1200 mcg over 48 hours.18 Whether these problems were caused by chromium picolinate or, if so, whether other forms of the mineral might have the same effects at these high amounts remains unclear. No one should take more than 300 mcg per day of the mineral without the supervision of a doctor.
Preliminary research has found that vitamin C increases its absorption.